I have just finished playing Simutrans for now and I remade a station and remodelled a complex junction and what I want to know is that why does the large ERTMS Signalling Centre have only a max capacity of 175 signals. Like modern day signalling centres irl don't have max capacity. Only a question but can the ERTMS Signalling Centre have unlimited signals please?

The idea of a maximum number of signals is that a signalbox has a finite capacity to control things. There is no easy way to code a finite capacity for controlling points, so the only variables that we can usefully use for a finite capacity are area or the number of signals.

Do you have data to suggest that the capacity of the ERTMS Centre as currently set is incorrect?

Because, on my fictional WCML and (6 or more signals) on the ECML, there are not enough signals to cover both routes (south of the border) and I think that me asking how to edit how much signals a control center could handle would be beneficial for me so I can add those missing signals. I would edit it to 200 signals.

Oh, you want to edit it yourself? I cannot remember the name of the parameter in the .dat files, but there is a .dat file reference on the forum somewhere that should tell you all about the various parameters for signalboxes. How to compile the pakset once you have made your changes is already explained in the tutorial on how to make additional liveries: the principle is the same.

In terms of the broader question of how the signal limits ought to be calibrated, it is not much use thinking about how many signals that an actual signalbox of the relevant type would control, as a real signalbox would control level crossing signals, shunting signals, repeaters, yard signals and many other things that are not directly simulated in Simutrans. The signal limit is instead intended to be proxy for an overall limit on scope of network that a signalbox can handle. This is much easier to calibrate for smaller signalboxes than larger signalboxes.

Thus, whilst it does not make sense to abolish the limit entirely as it has a specific purpose, if there be some reason to believe that the limit is too low and that some other specific higher number would better reflect how these sorts of signalling centres are used in reality, then I am certainly amenable to amending the limit - but cannot sensibly consider that without more detailed information as to the reason that the current limit of 175 signals (which is a lot for Simutrans) is too low. For example, if a real ERTMS signalling centre covers network of scope and complexity that is considerably greater than that which can be covered by one in game, then it would be reasonable in those circumstances to amend the signal limit to allow an ERTMS centre to control the same scope of network as it would be able to control in reality.

If anyone has any clear data on this, that would be most helpful. Otherwise, you might want to consider either using more ERTMS centres or an ERTMS centre combined with some smaller signalling facilities.

Modern control centres theoretically have no limits to the number of signals they can control thanks to computer technology. One could likely engineer one capable of managing hundreds of millions of signals if the need arises. What is more a limiting factor is what is it practical for a single centre to control.

The reason multiple centres are used in real life is for redundancy and failure limitation. Having a single control centre means a single point of failure for the entire network, similar to the star network pattern. By breaking control down into separate areas, possibly even with added redundancy, the maximum effect of a single point of failure would be the failure of only 1 region and not the entire network. Seeing how signal failure not only causes huge costly delays to train operators but also puts lives at risk it is well worth the added overhead of multiple centres to manage the network, even if the technology exists to control all signals in the entire network from a single centre.

Instead of defining some arbitrary limit, it would be better to define other limiting factors that force the construction and maintenance of multiple control centres. For example greater than 90% of signals controlled by control centres must be within 400 (or some number) tiles of a control centre, and that there must be at least 2 (or some number) control centres before any will work.

Another approach would be to have no limits but rather add a per signal cost to the centre, like there is in real life. The more a single centre controls, the higher its maintenance is. This could be applied per signal, or to the centre itself.

Just for comparison. There are only 2 control centers for the whole Czech Republic. I do not think they can serve as backup for each other. However they do not control the whole network. There are still man lines that are controlled locally. But the plan is to do it.

Maybe it is a usability problem? Perhaps the limit should be made globally where the maximum is defined by the number of centres and the current is total number of signals. Either the original topic creator was really fussy about maintenance costs, or they were complaining that simply building another centre was not a simple solution in this case.

Modern control centres theoretically have no limits to the number of signals they can control thanks to computer technology. One could likely engineer one capable of managing hundreds of millions of signals if the need arises. What is more a limiting factor is what is it practical for a single centre to control.

The reason multiple centres are used in real life is for redundancy and failure limitation. Having a single control centre means a single point of failure for the entire network, similar to the star network pattern. By breaking control down into separate areas, possibly even with added redundancy, the maximum effect of a single point of failure would be the failure of only 1 region and not the entire network. Seeing how signal failure not only causes huge costly delays to train operators but also puts lives at risk it is well worth the added overhead of multiple centres to manage the network, even if the technology exists to control all signals in the entire network from a single centre.

Instead of defining some arbitrary limit, it would be better to define other limiting factors that force the construction and maintenance of multiple control centres. For example greater than 90% of signals controlled by control centres must be within 400 (or some number) tiles of a control centre, and that there must be at least 2 (or some number) control centres before any will work.

Another approach would be to have no limits but rather add a per signal cost to the centre, like there is in real life. The more a single centre controls, the higher its maintenance is. This could be applied per signal, or to the centre itself.

Very true and I would like for it to be introduced to SImutrans Extended but of course priorities count! But I am not rushing for it to be added but still

I think that maybe for Signal Boxes/Signalling Centres having unlimited signals, add a per signal cost to the centre, like there is in real life.

Each signal has its own maintenance cost, so adding a maintenance cost to the signalling centre would be unnecessary and confusing.

As to limits, there needs to be a realistic incentive to build a realistic number of signalling centres, or else no player will ever build more than one for the whole world. That will be a balance problem, as the signalling cost will then be unrealistically low.

In real life the number of centres is determined by the need for redundancy as well as failure mitigation. In Simutrans your signalling centre will not burn down randomly or be destroyed by an Earthquake like they can be in real life. Hence there is no concern for redundancy or failure mitigation in Simutrans.

One could simulate this by forced mechanics. For example one needs at least 2 signalling centres for any signal to start working, and then every 1,000 odd signals an extra signalling centre. One can mention in documentation or in help that this limit is to reflect the need for redundancy.

These extra mechanics would require substantial extra coding and are a very low priority compared to several years' worth of additional features and bug fixes currently queued.

Also, having a separate redundancy mechanic for these signalling centres would make it much more difficult for players to understand the parameters and limitations than if the signalling centres had the same signalbox limitation mechanics as all other siganalboxes.